XXX-CR start up

[greyfox]

Have just bought a good second-hand Losi XXX -CR to get back into some fun club racing next year after quite a few years away from off-road.
Just need a bit of help/guidance on:-

What are the common breakages that I'll need to carry some spares for?
Looking to run an Xcelorin 10.5 combo (as I have one lying around at the moment) - as I'll be running outdoors on grass with a few jumps, is this a good motor to be starting with?
If so what ratio should I be looking for to begin with?
Finally any good hints/tips on set up - ie I've noticed elsewhere in another thread that about 10g's of lead should be added to the front to improve stability.

Thanks in advance for all your help and advice.